Field of the Invention
The present invention relates to a loading and/or unloading device for containers of irradiated fuel of a nuclear reactor or of a reprocessing unit of irradiated fuel, and it is more particularly concerned with the container transportation device, its positioning and sealing system underneath an unloading and/or loading pit, and to the traversing of the bottom of the pit of such a nuclear installation.
In order to make clear the problems solved by the device according to this invention, reference is first made to FIGS. 1A through 1H which illustrate schematically the various steps of a container loading operation. In these Figures, one sees at 10 a cart carrying the container 12 provided with a tight plug 14, said cart being moved outside the installation by a locomotor 16. Inside the installation, it is self-propelled, which allows bringing it in succession underneath a system 18 providing the removal of plug 14 and underneath a penetration shaft 20 acting as a lock with a pit or cell 22.
A loading operation includes the following steps:
1--bringing the container carrying cart to the removal station of plug 14 (FIG. 1B), after having previously passed through a preparation station; then PA0 2--moving the cart underneath penetration shaft 20 (FIG. 1C), in order to provide a path between pit 22 containing the irradiated fuel 24 and container 12, previously filled with water (FIG. 1D); PA0 3--the loading of container 12 with irradiated fuel 24 (FIG. 1E) is then carried out, then the container 12 is separated from pit 22, followed by the emptying of penetration shaft 20 (FIG. 1F); and finally PA0 4--the cart is transferred underneath the fitting and removal station of plug 14 (FIG. 1G), for resetting the sealing plug in position, followed by the carrying away of the loaded container (FIG. 1H).
The invention proposes a number of improvements to the various means used in this installation.